This invention is directed to an ion implantation system which has a separated ribbon beam ion source which has geometry which permits wafer traverse with minimum waste beam for maximum productivity and employs the same magnetic field source.
Prior ion implantation beam sources were comprised of separate functional components which were connected together to form the ion beam line. An ion source was used and it had its own magnetic field structure if such was required for the production of the ion beam. Ion separation downstream from the ion source required additional separation components. Due to the separate-element approach to the problems, the beam line is unnecessarily long and complex. These disadvantages are particularly bad in the case of high current low energy beams because severe space charge expansion occurs in the region between the ion source and separator. Attempts to locate the separator just downstream of the ion source were unsuccessful because the magnetic fields interferred. That is, the axial magnetic field in the ion source was disturbed by the transverse magnetic field of the separator.
With such a close coupled, compact ion source, a small surce chamber can be employed. A target chamber with a wafer wheel can be positioned directly adjacent thereto, and with associated equipment provide a compact ion implantation system.